KR20000069799A - Surface material for absorbent articles, absorbent articles that include the surface material, and the use of the material in absorbent articles - Google Patents

Abstract

The present invention relates to a surface material (5) for absorbent articles comprising a heat-shrinkable, spirally elastic thermoplastic multicomponent fiber (1), preferably a bicomponent fiber (1). The components (2,3) in the multicomponent fiber are located in parallel with one another with different shrinkage properties. The material consists of hydrophobic fibers and has an empty, air-permeable structure that quickly passes liquid in the absorbent article and transports it to the absorbent layer or sheet (7). Since the material has a smooth and smooth surface, it can be used for the seat 5 which will be placed close to the wearer in use. The invention also relates to an absorbent article comprising the surface material 5 and also to the use of this material as both a trapping / carrying sheet and a surface sheet in the absorbent article.

Description

Surface materials for absorbent articles, use of materials in absorbent articles and absorbent articles including surface materials

Absorbent articles are typically intended to be positioned close to the wearer in a layer or sheet of several materials, for example a liquid impermeable backing sheet, an absorbent layer or sheet disposed over the backing sheet, a capture layer / carrying layer thereon, and finally in use Surface sheet or top sheet. The trapping / carrying layer has an open air-permeable structure, which quickly absorbs a given volume of liquid and quickly transfers the liquid to the absorbing layer. This capture / carry sheet is polyester. Synthetic fibers, such as polypropylene fibers or mixtures thereof, may be made of a high swelling material that can be made by adhering or sewing through air. Since this layer or sheet has a rough and tingling surface, it is undesirable to have the layer directly contact the wearer's skin. Therefore, it is necessary to cover the upper surface of the capture sheet with a softer, more comfortable surface sheet. The surface sheet may be made of, for example, a nonwoven material.

Materials with other layers are known in the art, such as from SE-B-470 064. This publication teaches an absorbent fibrous structure comprising a sheet of bicomponent fibers and a superabsorbent material. The bicomponent fibers consist of heat-shrinkable, helical, elastic thermoplastic bicomponent fibers, and the fiber components have different shrinking properties and are placed in parallel relationship with each other. The superabsorbent material is in the form of particles and is maintained in the fibrous structure mainly by mechanical fixation at the turning point of the helical bicomponent fiber. This absorbent fiber structure is used for an absorbent sheet of an absorbent article, and the main purpose of the bicomponent fiber is to provide an absorbent sheet having a good absorbent property by holding a super absorbent material.

US-A-1,551,378 teaches nonwoven stretch fabrics. Knitted fabrics are made from mutually bonded bicomponent fibers by thermally contracting the fibers while fusing the fibers together at the point of contact. Since the fiber components have different shrinkage, when heated, they form a three-dimensional spiral. Knitted fabrics can be used as thermal insulators in sportswear and outdoor workwear.

EP-A1-0 306 262 and GB-A-2 214 201 teach, for example, absorbent structures in diapers and sanitary napkins. These structures include twisted fibers to add resilience to the structure and also to enhance resistance to wrinkling during use of the absorbent article.

Some problems with current absorbent articles are that the trapping / carrying sheets are expensive and their unpleasant contact with the skin results from their rough and tingling surfaces. Thus, a softer surface sheet is additionally needed for the human body, and as the work is done with additional sheets in the manufacture, the article becomes more expensive and more difficult to manufacture.

The object of the present invention is to solve these problems.

The present invention relates to surface materials for absorbent articles, such as diapers, sanitary napkins, urinary incontinence guards, panty liners and similar articles, absorbent articles comprising the surface materials and external sheets and capture / carry sheets integrated in absorbent articles. Related.

1 is a schematic diagram of a helical bicomponent fiber.

2A, 2B and 2C are enlarged cross-sectional views of three examples of fibers positioned next to each other taken on line II-II of FIG. 1, respectively.

3 is a schematic representation of helical bicomponent fibers fused to each other in some respects.

4 is a cross-sectional view of the urinary incontinence guard.

5 shows the urinary incontinence guard seen from above.

Fig. 6 is a photograph of one embodiment of the material of the present invention magnified 100 times with an electron microscope.

FIG. 7 is an enlarged photograph 1000 times the cross section of the fiber of the material shown in FIG.

Summary of the Invention

The present invention relates, in part, to surface materials for absorbent articles, such as diapers, sanitary napkins, incontinence guards, panty liners and the like, including heat-shrinkable, spiral, elastic thermoplastic multicomponent fibers, preferably bicomponent fibers. Spiral fibers provide an airy structure that is empty in the material, allowing the structure to quickly receive liquid and pass it through the surface sheet to transport to the underlying absorbent layer. The surface material also has a smooth and smooth surface.

The absorbent article of the present invention comprises a bottom liquid-impermeable sheet, an absorbent sheet and a top liquid-permeable surface sheet intended to be positioned close to the wearer in use.

The invention also relates to the use of the above-described materials as integrated surfaces and capture / carrying sheets in absorbent articles. Since the surface material has an empty air-permeable structure, it will serve as a capture / carry sheet. The sheet is also soft and smooth so that it can serve as a surface sheet at the same time.

The material is about 40-100 g / m², Preferably about 50-90 g / m²of It has weight per unit area.

The invention will now be described in more detail with reference to the accompanying drawings.

Detailed description of the invention

The surface material of the present invention is characterized in that it comprises heat-shrinkable, spirally elastic thermoplastic multicomponent fibers, preferably bicomponent fibers, wherein the fiber components are arranged in parallel relationship with each other with shrinkage. Heat-shrinkable, spirally elastic bicomponent fibers are shown in FIG. 1.

The present invention is described below with respect to bicomponent fibers.

Other types of bicomponent fibers parallel to each other can be used. FIG. 2A is a cross-sectional view of the fibers 1 in which the two components 2, 3 are located side by side, have an elliptical form and are stuck together along a part of the surface of each fiber. FIG. 2B illustrates another type of fibers in which components (2,3) are parallel to each other, similar to the example of FIG. 2A. In the latter case, however, the bicomponent fiber 1 has a circular cross section with an interconnection line across the cross section of the bicomponent fiber between the two components 2, 3. 2C shows a third type of fiber that is an eccentric sheath-core fiber. The first component 2 of the fiber 1 takes the form of an eccentrically laid core surrounded by the shell of the second component 3. Since the core comprising the first component (2) lies within the second component (3), the second component will be hollow if some surface of the first component (2) lies on the face or boundary of the bicomponent fiber. Thus, the first component 2 will have a part of the outside laid free.

Bicomponent fibers are generally round in shape, but fibers having other cross-sectional shapes are possible, such as fibers having elliptical, trilobal or rectangular cross-sectional shapes.

It is essential that the selected fiber components have different shrinkage properties. When heat is applied to a bicomponent fiber having this property, each of the bicomponent fibers will shrink to a different degree, so that one side of the fiber will be shorter than the other, which causes the fibers to twist and shrink so that the spiral Will be in form. A bicomponent fiber suitable for this purpose is marketed by Chisso Corporation, Osaka, Japan under reference EP-HS P2. This fiber is a 1.7 dtex shrinkage, molten fiber composed of two different polypropylenes, each having a high melting point and a low melting point. This fiber is of the side by side type shown in Figure 2c.

Surface materials consisting of these bicomponent fibers are produced, for example, by carding goose fabrics from parallel fibers and oven-bonding. Staple fibers having a length of 30-60 mm, preferably 40-50 mm are used. Since the fibrous component will shrink to a different degree, the bicomponent fibers will be twisted and shrunk to form a spiral. Heat-treated and bonded sheets will be thicker than carded yarn entering the oven because the bicomponent fibers are helical and an airy structure is added to the sheets. Since the bicomponent fibers are melted during the heat-treatment process, the fibers also serve as binders in the actual fiber structure. Thus, as shown in FIG. 3, the spirals will melt and fuse with each other at separate points of the spiral. The bicomponent fibers 1 are bonded to each other at a point 4.

The surface material is suitably made of hydrophobic fibers. Spiral fibers provide an empty structure for the surface material. This means that the material does not absorb the liquid, but instead can quickly capture and transport the liquid into the product. Thus, the surface material serves as a trapping / carrying sheet in the absorbent article. Since the surface sheet allows the liquid to pass quickly, the surface of the sheet will feel dry on the wearer's skin when in use. Movement of liquid on the product surface is prevented.

The surface material of the present invention is soft and smooth as opposed to current trapping / carrying sheets. The material is made from fibers having a thickness of about 1.5-3.3 dtex, preferably 1.7-2.5 dtex. These fibers are relatively thin compared to typical fibers having a thickness of about 6 dtex mixed with binding fibers having a thickness of about 4 dtex used in conventional trapping / carrying sheets. The coarser the fiber, the harder and stiffer the material. This conventional sheet is too stiff and too stingy for use in direct contact with the wearer's skin. However, the thickness of the fiber disclosed above is essential for adding sufficient airy or empty structure to the conventional material to serve as a trapping / carrying sheet. The bicomponent fibers having a thickness of about 1.5-3.3 dtex used in the present invention make the material smoother and softer than conventional materials so that the material of the present invention can be placed closer to the wearer's skin and contacted. As can be seen, the sheet serves both as a capture / carry sheet and as a surface sheet, thus eliminating the need for the original additional surface sheet.

FIG. 6 is a photograph illustrating one embodiment of an invention material made from bicomponent fibers marketed by Chisso Corporation of Osaka, Japan, having a thickness of EP-HS P2, 1.7 dtex. Bicomponent fibers are shrink-melted fibers consisting of two different polypropylenes.

In the picture, the fibers are magnified 100 times. It will be seen in the picture that the fibers are spiraled as a result of heat treatment.

FIG. 7 is a photograph of the same material as shown in FIG. 6 except that it is enlarged 1000 times. The photograph shows a cross section of the fibers, which will show that the fibers are in parallel with each other according to FIG. 2C. Component 2 is shown as the core and component 3 is arranged around the core. Component 3 is melted by heat-treatment and flows to completely cover the core consisting of Component 2.

It is essential that each of the two components 2, 3 in the shrink-proof fiber 1 shrinks to a different degree when heated. This shrinkage imbalance will spiral the prestressed fibers. The preshrunk bicomponent fiber 1 is very stretchable and elastic, providing a reasonable limit of free movement in the sheet. Thus the material can be easily shaped in the finished product and will fit the wearer's body in a comfortable form.

In one preferred embodiment, the components 2, 3 of the bicomponent fiber 1 consist of different types of polyethylene having different melting points and shrinkage.

In another embodiment, the components (2,3) of the bicomponent fiber 1 are polypropylene and polyester, respectively.

In another embodiment, the surface material also includes thermoplastic binding fibers, such as polypropylene or polyethylene.

Various polymers may also include other homopolymers or copolymers. Examples of polymers that can be used in this regard are polyolefins, polyamides, copolyamides, polyesters, copolyesters, polyacryl and the like. The polymer may also include any other conventional additives, such as softeners, according to known practice. It is a feature of the present invention that the two components (2, 3) of the bicomponent fiber (1) have different shrinkage properties.

Also contemplated are embodiments comprising mixtures of other bicomponent fibers.

When the surface material contains only bicomponent fibers, it will have a highly empty, airy structure. In the case of the embodiment where the material also comprises thermoplastic bonded fibers, these fibers will not shrink but will be spiraled in the same way as bicomponent fibers. Thus, the sheet comprising the bond fibers will not be as empty or airy as the sheet comprising only the bicomponent fibers, and will not be thick. Binding fibers can be used to control or control the thickness and void of the sheet. When the material comprises binding fibers, the binding fibers are carded with the bicomponent fibers to form a high ozone and then oven bonded.

The invention also comprises a diaper, sanitary napkin, incontinence guard, pantyliner or a liquid-impermeable backing sheet 6, an absorbent sheet 7 and a liquid-permeable surface sheet or topsheet 5 positioned close to the wearer in use. Absorbent articles, such as analogous articles, the absorbent article wherein the surface sheet material comprises heat-shrinkable, spirally resilient thermoplastic bicomponent fibers (1), wherein the components (2,3) of the bicomponent fibers have different shrinkage properties. It is characteristic in that it is located side by side with each other. The surface sheet is made of the sheet material of the present invention as described above.

4 is a cross section of an incontinence guard comprising a surface sheet 5 of the invention. The incontinence guard also includes a liquid-impermeable backing sheet 6, an absorbent sheet 7 behind the backing sheet, and a liquid-permeable topsheet or surface sheet 5 intended to be positioned close to the wearer when used on the absorbent sheet 7. Include. The upper surface sheet 5 consists of the heat-shrinkable, spirally elastic thermoplastic, and also hydrophobic bicomponent fibers 1. The surface sheet has an empty air-permeable structure and also has a smooth and smooth surface. The top surface sheet also serves as a trapping / carrying sheet, and quickly passes the liquid and carries it to the absorbent sheet 7. The surface sheet is smooth and soft and can be placed comfortably on the wearer's skin. Thus, the surface sheet 5 faces the wearer and, when wearing the absorbent article, is intended to be placed in contact with the wearer's skin and forms both the surface sheet and the capture / carry sheet.

5 illustrates the embodiment of another incontinence guard from above. The incontinence guard consists of a liquid-impermeable bottomsheet 6, an absorbent sheet or layer 7 and a liquid-permeable topsheet or surfacesheet 5 positioned close to the wearer in use. The surface sheet 5 consists of two materials, the first being the surface material 8 of the present invention and the second being the nonwoven material 9. The surface material 8 of the present invention is placed in the wetted area and the hydrophobic nonwoven material 9 is placed at the edge of the incontinence guard around the surface material 8 of the present invention. The nonwoven material 9 is essentially liquid impermeable and is intended to prevent backflow of the liquid from the absorbent layer so that no liquid can penetrate to the side of the article. The nonwoven material can be bonded together with the surface material of the invention, for example.

The invention also relates to the use of said material consisting of heat-shrinkable, spirally resilient thermoplastic bicomponent fibers (1) in which the components (2,3) of the fibers are placed side by side (or in parallel with each other) with different shrinkage properties. . The material may be a diaper, sanitary napkin, incontinence guard, pantyliner or similar article comprising an absorbent sheet or layer 7 and a liquid-impermeable backing sheet 6 underneath the integrated surface sheet and the capture / carry sheet 5. It is used as an integrated surface sheet and capture / carry sheet in absorbent articles such as.

As noted above, the material comprising the heat-shrinkable, helical, resilient thermoplastic bicomponent fiber 1 will have a highly airy, highly hollow structure. Since the fibers are hydrophobic, the material will not absorb the liquid, but instead will quickly pass the liquid and transport it to the absorbent sheet 7. The material of the present invention has a smooth and smooth surface. Thus, the material can be used in a sheet positioned close to the wearer in use without the skin of the wearer peeling off and without making the user feel uncomfortable. This material can be used both as a trapping / carrying sheet and as a surface sheet. This is an advantage compared to the materials currently used for this purpose. Since the current capture / carry sheets have a tingling and rough surface, they are not suitable for use in applications where such sheets are in direct contact with the wearer's skin. This means that additional surface sheets are needed for conventional articles. The material of the present invention eliminates the need for such additional surface sheets.

It is to be understood that the invention is not limited to the embodiments thereof described and illustrated, and that further modifications are possible within the scope of the following claims.

Claims (22)

In surface materials for absorbent articles such as diapers, sanitary napkins, urinary incontinence guards, panty liners and similar articles, the surface material (5) is heat-shrinkable, spiral, elastic thermoplastic multicomponent fibers (1), preferably bicomponent fibers (1). ), Wherein the hydrophobic component (2,3) in the fiber is positioned in a side by side relationship with different shrinkage properties. 2. The surface material according to claim 1, wherein the components (2,3) in the bicomponent fibers (1) are each composed of different types of polypropylene. 2. The surface material according to claim 1, wherein the components (2,3) of the bicomponent fibers (1) are polypropylene and polyester, respectively. 2. The surface material of claim 1, wherein the material comprises a mixture of bicomponent fibers. 5. Surface material according to any of the preceding claims, wherein the material also comprises thermoplastic bonded fibers such as polypropylene or polyethylene. 6. Surface material according to any of the preceding claims, wherein the bicomponent fibers have a thickness of about 1.5-3.3 dtex, preferably 1.7-2.5 dtex. 7. Surface material according to any one of the preceding claims, characterized in that the material has a weight per unit area of about 40-100 g / m ² , preferably 50-90 g / m ² . Diapers, sanitary napkins, urinary incontinence guards, panty liners or the like comprising a liquid-impermeable backing sheet 6, an absorbent sheet or layer 7 and a liquid-permeable top surface sheet 5 intended to be positioned close to the wearer in use; In the same absorbent article, the surface sheet material comprises heat-shrinkable, helical, elastic thermoplastic multicomponent fibers (1), preferably bicomponent fibers (1), wherein the hydrophobic components (2,3) in the fibers are different. Absorbent article, characterized in that located in a side by side relationship with shrinkage. 10. The absorbent article according to claim 8, wherein the surface sheet (5) forms an integrated surface sheet and a trapping / carrying sheet. 10. The absorbent article as set forth in claim 9, wherein the components (2,3) in the bicomponent fiber (1) consist of different types of polypropylene. 10. The absorbent article as set forth in claim 9, wherein the components (2,3) in the bicomponent fiber (1) are polypropylene and polyester, respectively. 10. The absorbent article as in claim 8, wherein the surface sheet material comprises a mixture of bicomponent fibers. 13. An absorbent article according to any of claims 8 to 12, wherein the surface material (5) also comprises thermoplastic bonded fibers, such as polypropylene or polyethylene. 14. The absorbent article of claim 1, wherein the bicomponent fiber has a thickness of about 1.5-3.3 dtex, preferably 1.7-2.5 dtex. 15. The absorbent article of claim 1, wherein the surface sheet has a weight per unit area of about 40-100 g / m ² , preferably 50-90 g / m ² . Incorporated in absorbent articles such as diapers, sanitary napkins, incontinence guards, panty liners and similar articles comprising an absorbent sheet (7) and a liquid-impermeable backing sheet (6) under the integrated surface sheet and capture / carry sheet (5) Surface sheet and trapping / carrying sheet (5), comprising heat-shrinkable, spiral, elastic thermoplastic multicomponent fibers (1), preferably bicomponent fibers (1), wherein the hydrophobic components (2,3) of the fibers The use of materials characterized in that they are placed side by side with different shrinkage properties. Use of a material according to claim 16, wherein the components (2,3) of the bicomponent fibers (1) are different polypropylenes. Use of a material according to claim 16, wherein the components (2,3) of the bicomponent fibers (1) are polypropylene and polyester, respectively. 17. The use of a material according to claim 16, wherein the material comprises a mixture of bicomponent fibers. 20. Use of a material according to any one of claims 16 to 19, wherein the material further comprises thermoplastic bonding fibers such as polypropylene or polyethylene. The use of a material according to claim 1, wherein the bicomponent fibers have a thickness of about 1.5-3.3 dtex, preferably 1.7-2.5 dtex. 22. Use of a material according to any of claims 1 to 21, wherein the material has a weight per unit area of about 40-100 g / m ² , preferably 50-90 g / m ² .